论文部分内容阅读
为了探索大麦耐低氮的生理机制,以诱变小孢子+氮胁迫培养获得的与原始品种氮素利用率差异显著的突变体(‘A1-97’和‘A1-57’)和原始对照品种‘花30’为材料,在盆钵栽培中进行了高低两种氮素水平处理,分析了植株在苗期、灌浆期和成熟期的碳氮代谢关键酶活性。结果显示,相比原始对照品种‘花30’,2份突变体材料的碳氮代谢酶活性在灌浆期有更显著的差异,表明灌浆期可能是研究耐低氮的关键时期;低氮水平下,灌浆期氮素利用率高的突变体‘A1-97’硝酸还原酶活性和谷氨酰胺合成酶活性皆显著增强,氮素利用率低的突变体‘A1-57’硝酸还原酶活性显著降低,谷氨酰胺合成酶活性差异不显著;灌浆期和成熟期的突变体‘A1-57’蔗糖磷酸化酶活性显著降低。由此推测,突变体与原始品种间耐低氮性的差异可能与硝酸还原酶、谷氨酰胺合成酶和蔗糖磷酸化酶活性存在一定的联系。
In order to explore the physiological mechanism of low nitrogen tolerance in barley, mutants (’A1-97’ and ’A1-57’) significantly different in nitrogen use efficiency from the original cultivars obtained by mutagenesis microspore + nitrogen stress and original control varieties ’Hua30’ was used as material, and two high and low nitrogen levels were applied in pot cultivation. The key enzyme activities of carbon and nitrogen metabolism were analyzed at the seedling, filling and maturing stages. The results showed that compared with the original control cultivar ’Hua’30, the two mutants showed more significant differences in carbon and nitrogen metabolism enzyme activities at grain filling stage, indicating that grain filling may be the key period to study low nitrogen tolerance. Under low nitrogen levels , The nitrate reductase activity and glutamine synthetase activity of ’A1-97’ mutants with high nitrogen utilization rate at grain filling stage were significantly enhanced, and the activity of ’A1-57’ nitrate reductase with low nitrogen utilization rate was significantly decreased , While the activity of glutamine synthetase was not significant. The activity of mutant ’A1-57’ sucrose phosphorylase at grain filling stage and mature stage was significantly decreased. Therefore, it is speculated that the difference of low nitrogen tolerance between mutants and original cultivars may be related to the activity of nitrate reductase, glutamine synthetase and sucrose phosphorylase.